On Nov 29, 2011, at 6:55 PM, Bloch Stephen wrote:
>> On Nov 29, 2011, at 4:31 PM, David Van Horn wrote:
>>> On 11/29/11 4:28 PM, Jakub Hadam wrote:
>>> Hello,
>>> I claim there is a typo in the online version of HtDP:
>>> Exercise 4.3.3, the first condition should be
>>>>>> [(<= n 1000) (* .040 n)]
>>>>>>>>>>>> instead of
>>>>>> [(<= n 1000) (* .040 1000)]
>>>> Why? That's what's in the printed book too and it seems perfectly reasonable to me.
>> Well, it's a "what is the value of this expression?" exercise, so technically it could have been anything. However, to solve the intended problem of bank interest, Jakub is right: it should be (* .040 n) in the first case (otherwise people would earn the same $40 interest on a deposit of a penny as on a deposit of $1000.)
>
The exercise is intentionally formulated this way. I am glad you discovered the twist. -- Matthias